Question about skill modifiers

I can seem to find this information anywhere.

In the Demo skill tree Static Strike gives (+%fire damage) now does this only apply to the Fire Strike skill or does it also apply to other skill lines such as Mortar Trap?

Only to fire strike.

in general, damage modifiers like that on a passive piece attached to an active skill will only effect that skill. If it effects everything, it will usually say explicitly.

For example, on lethal assault:

It says “Lethal Assault affects all attacks while active.”

Thanks for the information!